Condensed Consolidated Statements of Changes in Equity (unaudited) - USD ($) $ in Millions	Total	Total Baxter stockholders' equity	Common stock	Common stock in treasury	Additional contributed capital	Retained earnings	Accumulated other comprehensive income (loss)	Noncontrolling interests
Balance, beginning of period (in shares) at Dec. 31, 2023			683,000,000
Balance, beginning of period (in usd) at Dec. 31, 2023	$ 8,468	$ 8,402	$ 683	$ (11,230)	$ 6,389	$ 16,114	$ (3,554)	$ 66
Balance, treasury, beginning period (in shares) at Dec. 31, 2023				176,000,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(128)	(137)				(137)		9
Other comprehensive income (loss)	(97)	(93)					(93)	(4)
Stock issued under employee benefit plans and other	148	148		$ 146	2
Dividends declared on common stock	(448)	(448)				(448)
Stock issued under employee benefit plans and other (in shares)				(3,000,000)
Change in noncontrolling interests	(1)							(1)
Balance, end of period (in shares) at Sep. 30, 2024			683,000,000
Balance, end of period (in usd) at Sep. 30, 2024	7,942	7,872	$ 683	$ (11,084)	6,391	15,529	(3,647)	70
Balance, treasury, ending period (in shares) at Sep. 30, 2024				173,000,000
Balance, beginning of period (in shares) at Jun. 30, 2024			683,000,000
Balance, beginning of period (in usd) at Jun. 30, 2024	7,708	7,643	$ 683	$ (11,104)	6,353	15,539	(3,828)	65
Balance, treasury, beginning period (in shares) at Jun. 30, 2024				173,000,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	144	140				140		4
Other comprehensive income (loss)	181	181					181	0
Stock issued under employee benefit plans and other	58	58		$ 20	38
Dividends declared on common stock	(150)	(150)				(150)
Change in noncontrolling interests	1							1
Balance, end of period (in shares) at Sep. 30, 2024			683,000,000
Balance, end of period (in usd) at Sep. 30, 2024	7,942	7,872	$ 683	$ (11,084)	6,391	15,529	(3,647)	70
Balance, treasury, ending period (in shares) at Sep. 30, 2024				173,000,000
Balance, beginning of period (in shares) at Dec. 31, 2024			683,000,000
Balance, beginning of period (in usd) at Dec. 31, 2024	$ 7,024	6,964	$ 683	$ (11,059)	6,421	14,929	(4,010)	60
Balance, treasury, beginning period (in shares) at Dec. 31, 2024	172,567,636			173,000,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	$ 171	171				171		0
Other comprehensive income (loss)	162	162					162	0
Stock issued under employee benefit plans and other	92	92		$ 168	(76)
Dividends declared on common stock	(263)	(263)				(263)
Reclassification of other comprehensive income (loss) disposed in the Kidney Care separation	115	115					115
Stock issued under employee benefit plans and other (in shares)				(3,000,000)
Disposition of noncontrolling interest associated with the Kidney Care separation	(87)							(87)
Balance, end of period (in shares) at Sep. 30, 2025			683,000,000
Balance, end of period (in usd) at Sep. 30, 2025	$ 7,214	7,241	$ 683	$ (10,891)	6,345	14,837	(3,733)	(27)
Balance, treasury, ending period (in shares) at Sep. 30, 2025	169,548,900			170,000,000
Balance, beginning of period (in shares) at Jun. 30, 2025			683,000,000
Balance, beginning of period (in usd) at Jun. 30, 2025	$ 7,293	7,320	$ 683	$ (10,915)	6,328	14,970	(3,746)	(27)
Balance, treasury, beginning period (in shares) at Jun. 30, 2025				170,000,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(46)	(46)				(46)		0
Other comprehensive income (loss)	13	13					13
Stock issued under employee benefit plans and other	41	41		$ 24	17
Dividends declared on common stock	(87)	(87)				(87)
Balance, end of period (in shares) at Sep. 30, 2025			683,000,000
Balance, end of period (in usd) at Sep. 30, 2025	$ 7,214	$ 7,241	$ 683	$ (10,891)	$ 6,345	$ 14,837	$ (3,733)	$ (27)
Balance, treasury, ending period (in shares) at Sep. 30, 2025	169,548,900			170,000,000